As Craig said...and it's also possible that this is more than just one missed shed on her tail tip, and in that case, you could end up with the actual tail tip coming
off like a scab, leaving exposed skin (that could use some antibiotic attention). This is how tail tips are lost in snakes...retained sheds constrict the blood flow in
the tail tip (which is already poor), & then the tissue dies. This is why we "nag" everyone to check eyes & tail tips after every shed, to make sure that everything
came off that should have. Tail tips do not grow back. And if this IS just shed skin that hasn't yet permanently damaged the actual tail tip, do be gentle when helping the old shed skin off...it might be "borderline" and the tail tip can be saved.